Network virtualization, as an important technology in a future network architecture, is expected to integrate different physical resources on the basis of an existing physical infrastructure to provide an efficient and independent network service environment according to requirements. As a network environment, the network virtualization technology allows a service provider to dynamically construct multiple heterogeneous virtual networks on a same physical infrastructure, where the virtual networks coexist and are independent of each other. In addition, the network virtualization technology allows owners of the virtual networks to dynamically deploy and manage customized end-to-end services for users in their virtual networks in real time.
Virtual network migration is an important technology for network virtualization. By using the virtual network migration technology, a mapping relationship of a virtual network on a physical network may be dynamically adjusted according to a cause that triggers migration, and an operator is allowed to dynamically plan physical resources and traffic management according to requirements, and improve resource utilization of the physical infrastructure. Meanwhile, according to the change of state information of the physical network and service requirements of the virtual network, a single node or a part of nodes of the virtual network may be dynamically re-deployed to meet the traffic or service requirements and reduce unnecessary physical loss and energy consumption.
The cause that triggers virtual network migration may be analyzed from internal and external aspects.
The external causes include failure to satisfy a new virtual network request, change of a service requirement, and so on.
When a new virtual network request arrives, because utilization of a part of physical infrastructures in the existing physical network is high, which cannot satisfy the mapping requirement of the virtual network, the mapping of the existing virtual network may be replanned, so that utilization of network resources is more reasonable and that idle physical network resources satisfy the new virtual network request.
When the service requirement is changed, the physical infrastructure of the source virtual network may fail to satisfy the new requirement and may cause virtual network migration to search for more suitable mappings on the physical topology.
The internal causes include: migration of a virtual node in the virtual network, which is caused by sudden system breakdown, migration of a virtual link in the virtual network, which is caused by link damage, virtual network migration caused by device upgrade, virtual network migration caused by a load balance problem, and so on.
In the prior art, when a physical node needs to perform virtual network migration, first a virtual node of the physical node is obtained, and then in the original physical network architecture, a suitable new physical node is found in the vicinity of the physical node, and a virtual link is established between the source physical node and the new physical node for virtual network migration.
In the existing technical solution, search of a new physical node is limited to search of a new physical node in only the vicinity of the physical node in the original physical network architecture. However, if usage of the original physical network resources is high, it is hard to find a suitable new physical node for virtual network migration. Therefore, the possibility of migration failure is high. Furthermore, search of a new physical node in this solution is based on a shortest path principle (that is, searching for a new physical node in the vicinity of the physical node), but the search method does not consider usage of resources of the new physical node; after virtual network migration, it is quite possible that usage of resources of the new physical node is too high but usage of resources of other physical nodes in the physical network is very low, resulting in unreasonable resource allocation and low network operation efficiency.